The role of a crime scene investigator is very different from how it's portrayed in popular television shows and movies. Unlike their fictional counterparts, real-life crime scene investigators don't single-handedly collect and analyze all of the evidence, question witnesses and suspects, and identify the perpetrator. Instead, their role is an essential part of the team effort it takes to unravel the many aspects involved in a crime.

Identifying and Preserving Evidence

Crime scene investigators start their investigation by walking through the scene of a crime and determining what should be collected as evidence. They also determine the best way to collect the evidence without disturbing the rest of the crime scene and without hindering the ability of officers to investigate the scene. Their training and experience allow them to identify clues that others might miss, either because the piece of evidence is so small or because it's not obviously related to the crime. They also preserve evidence by sealing it in sterile containers or plastic bags to maintain its integrity.

Documenting Evidence

Crime scene investigators document everything they collect at a crime scene, keeping detailed records of what they found and in what position they found it. They also photograph every aspect of the crime scene, from the victim's body in the case of a violent crime, to the point of entry in the case of a burglary. Detectives use these records and photographs to reconstruct the crime, and prosecutors use them to convince a jury of the guilt of the accused. These records are also vital in case a piece of evidence gets lost or becomes damaged during the investigation.

Collaborating With Other Law Enforcement

Crime scene investigators work closely with others involved in the case, including detectives and prosecutors. This relationship is crucial to crime-solving, as the various parties pool their knowledge to develop leads and theories. If crime scene investigators can point out key pieces of evidence while still at the crime scene, this helps officers determine early on the possible angles to pursue in their investigation. Police can ask crime scene investigators to conduct specific tests to help them with their investigation. For example, a detective might ask a crime scene investigator to compare fingerprints or DNA found at the scene to determine if they match the suspect.

Testifying in Court

Crime scene investigators are sometimes required to provide expert testimony in legal proceedings. They explain what evidence was found and what it means regarding how a crime was committed, how a victim died or who was responsible. They explain these details in a way so the jury members, who likely have little to no legal or law enforcement knowledge, can understand the significance. Prosecutors call on crime scene investigators to provide testimony that will support their claim against the person on trial.